Hydraulic variable and differential speed gear.



A. SUNDAH. HYDRAULIC VARIABLE AND DIFFERENTIAL SPEED GEAR.

APPLICATION FILED MAY17.1909. LQW WAA EatentedNov. 28,1916

4 SHEETSSHEET1.'

A. SUNDH.

HYDRAULIC VAR'I ABLE AND DIFFERENTIAL SPEED GEAR.

APPLICATION FILED MAYH. 1909.

4 SHEETS-SHEET 2.

Q W lmeowo A. SUNDH. HYDRAULIC VARIABLE AND DIFFERENTIAL SPEED GEAR. APPLICATION FILED MAY 17, 1909.

4 SHEETS-SHEET 3.

Patented Nov. 28

I I'I A All I! IIIIIIIIVVIIIIIII!!! A. SUNDH. HYDRAULIC VARIABLE AND DIFFERENTIALSPEED GEAR.

APPLICATION FILED MAY I7, 1909 Patented Now 28, 1916.

4 SHEETS-SHUT 4.

I Q'URRW 1? mamas means for differentially Application filed May it,

To HUM/710772, it may] concern:

lie it known that T, AUeUs'r honor-r, a citizen of the United States, residing in i'onlrers. in the county of l l estchester and ate or New York, have invented a new and useful improvement in'li-lydraulic Variable and Differential Speed Gears, of which the following is a specification.

lily invention relates to mechanisms tor transmitting power by fluid pressure, and comprises means for varying the amount of power transmitted, and also comprises varying the speed oi the driven mechanism.

One of the objects of the invention isto obtain power transmission mechanism .of this character. which issimple in construction. etlicient in operation and in which a gradual variation in the power may be obtained throughout a wide range.

i t further object of the invention is to reduce the size of the mechanism to a minimum, and make the same self-contained, so that the same may readily be connected between a prime mover or source of power and the machinery to be driven.

it. still furtl'icr object of the invention is to obtain tl'uid power transmission mechanism which may be used not only as a variable speed gear, but also as a brake, and which may further be used as a steering apparatus- The invention is adapted for use on automobiles, motor boats, differentially driven elevators; and various other devices.

Referring to the accompanying drawings in which is illustrated. a construction embodyinp; my invention Figure 1 is a plan view of the power transmission mechanism with the top cover of the inclosing; caslng removed: Fig. 2 .is a sectional elevation.

taken substantially on theline 2-2 of Fig.

1; Fig. 3 is a sectional plan view of the drivinir shaft and parts associated therewith: Fig. 4- isasectional elevation throughthe pressure and supply tanks and taken on the line 4l-l of Fig 1; l? ,5 is a trag-' mentary view showing a motor'valve and the eccentric for operating the same; Figs. t: and '7 are similar views showing the'eccentric adiusted toditterent positions; Fig. 8 is a detail view of means tor'a'djusting the eccentric; Fig. 9 is a'sectional plan view of the eccentrics :t'or operating-the motor valves and means for adjusting'said eccen- SUNDH, GE EEUNKERS, Nlillllf YDlitlil, AS-ETGNO' E CITY, NEN JERSEY, A 60kt.

DIFZEEREJFY[111A]; ELP'IEEIIQ G15 Specification of Letters Patent.

tion of the casing, and has keyed thereto at its opposite ends sprocket wheels 2 and 3, which may be connected by sprocket chains 4;. and 5 respectively with a prime mover such as an electric motor, an internal coinbustion engine or any other suitable source oil power, the exact nature of which will of course dependupon the particular use to which the invention is applied. The means for gearing the shaft 1 to a source 0t power may be varied. as desired. The shaft Tl. opcrates the eccentrics Til y and ill which drive the pumping mechanism T The lat ter draws liquid from the supply chamb and forces it under pressure into the prov-- sure chamber T. The liquid from the pressure chamber "is circulated through in torsll l and M and from thence back into the supply chamber The motors M and M- dive the cranl: shafts 7 and 8 respec tively to which are'keyed the gear wheels i: and 10, adapted to be geared to the driven. mechanism.

Within the driving shaft 1, which is hollow as shown in Fig. 3. is a rod 11 adjustable longitudinally within the shatt. @ppo site each of the eccentrics E, E and E the rod 11 is formed with oppositely disposed slots or recesses 12 and 13; The base oi each slot is inclined in the same direction so that a web 14: is formed between each pair at slots.

The eccentrics E, E and E are substantially alike in construction, and each 0011'): prise s a ring or sleeve 15. l l ithin the sleeve 15 arev studs or earns 16 and 17?. the outer ends of which are threaded into the ring 15. These studs extend into the recesses 12 and 13,, and their inner ends are inclined to correspond to'the web 14. Surrounding; each eccentric ring 15 is an eccentric strap sefcured to the outer end 01'' a. piston rod 19.

the inner end of which is pivoted at 20 to a piston 21 adapted. to reciprocate in a pump cylinder -22.

I The rod 11 is normally held in the position shown in Fin". 3 b 1 means at a coil "spring 23, the inner endof which bears rounding the eccentric 30.

chamber 36.

agalnst the rod 11. "The outer end of the spring 23 bears against a stud bolt 24 threaded into the end of the driving shaft 1, and which also serves to hold the gear wheel 3 in position. The opposite end of the rod 11' is preferably provided with packings 25-so as to prevent leakage when the rod 11 is operated by liquid pressure as a piston within the hollow shaftor cylinder 1 as will presently be described. Extending from the right hand end of the rod or piston 11 is a rod 26 of reduced in the piston 11, and held in adjusted position by a setnut 27. 'The-outer end of the rod 26 bears against the plug 28 which is preferably a tight fit within the hollow shaft 1. A stud bolt 29 threaded into the shaft bears against the plug 28 and also serves to hold the gear Wheel 2 on the shaft. Keyed to the drive shaft 1 is an eccentric 30 adapted to drive a small pump D. The latter comprises a cylinder 31 in which is adapted to reciprocate a piston 32 connected by a link 33 to the eccentric strap 34 sur- The operation of the-\purnp D is controlled by a valve 35 slidable within the valve chamber 36. Passages 37 and 38 leadfrom'the pump cylinder to the valve chamber 36. A pipe 39 leads from the passa e 38 to the supply chamber S. The pump .cy inder 31, the passages 37 and 38 and the case for the valve 35 are preferably formed in a single casting D. This casting has a portion 40' surrounding the shaft 1, and provided'with an annular passage 41 connected bya passage 42 with the valve A sleeve or bushing 43 is secured to the driving shaft 1, and rotates therewith. This sleeve and shaft 1 are provided with ports establishing communication between the interior of the shaft. 1, and the annular passage 41. The pump D is operated continuously While the shaft 1 is rotating. When the valve 35 is in the position b shown, the pump piston 32 during its in- ,.wa'rd movement forces the liquid past the the passages 37 and.42. Th

check valve 45 through the passage-37 into the valve chamber 36, and from thence through the passage 38 and pipe 39 to the During the outward 32, theliquid is drawn from the supply chamber Sthrough pipe 39, passage 38 and past the check valve 46 into the pump cylinder. In order to effect an adjustment of the eccentrics E, E and E the valve 35 is moved outward, so as to establish communication between the e inward movement of the pump piston 32 will then force the liquid through the passages 37, 42 and 41 into the hollow shaft 1. As the pump piston moves outward the check valve 45 prevents a return flow of the liquid from the shaft 1,

and liquid is drawn from the supply chamdiameter, adjustable withvE, E and end of the valve.

in the form of mo es? her through the pipe 39, passage 38 and past the check valve 46 into the cylinder 31 to he forced into the hollow shaft 1 on the next inward stroke of the piston. The liquid as it is thus pumped into the shaft 1 forces the piston rod 11 to the left, and'the cam studs 17 are forced outward by the inclined webs 14, thereby moving the eccentrics from a position concentric with the driving shaft as shown to an eccentric position. During this adjustment of the eccentrics, the cam studs 16 of course maintain the same'relotive posi tion with respect to the cams 17, or in other words remain in contact with or in close proximity to the webs 14, so rod 11 is moved to the right, the webs 14 force the cams back toward a concentric position. The piston valve 35 controlling the pump D is provided with a valve stem 50 provided atits outer end with rack teeth 51, Fig. 10. An arm 52 secured to a pivot stud 53 journaled in the side of the casing A is provided with rack teeth meshing with the rack teeth 51 on the valve stem. The arm 52 is rocked to adjust the position of the valve by means of a hand lever 54 secured tothe pivot stud 53. The lever 54 is held in any desired position by means of a latch or pawl 56 engaging with rack teeth 57 formed on a segmental rack bar 58 bolted to the cusing A concentric with the pivot 53. The latch 56 is operated by an ordinary latch lever 55. In order to adjust the eccentrics E toward a central position, the hand lever 54 is moved forward from the central position, shown in Fig. 10, thereby moving the valve 35 farther inward.- This brin s the passage 42 into communication with-a by-pass 59 extending around the outer The spring 23, which is under compression, now forces the rod 11 to the right, forcing the liquid'in front of said rod out through the passages 42, 59, 38 and through the pipe 39 to the supply chamer. It Wlll be seen that the eccentrics may be adjusted to any desired intermediate position, and when in such position are prevented from further movement in either direction by'locking the hand lever 54 in its central position as shown. In

the spring 23 holds the rod 11 as far to the right as the remaining liquid in the shaft will permit' he pressure and supply chambers T and S are comprised in a casing 60 separated into two compartments by the partition 61 extending longitudinally through the casing 60. The latter is provided with side flanges 62, and end flanges 63 bolted to a base or frame 64. It will be observed that this frame 64 which is bolted or otherwise secured to the bottom of the outer casing A is a rectangular plate covering that when the L flail (it. forms a support for her S and the pump cyl I stroke the valve77 substantially the entire bottom surface of the casing" A. with the exception of cutaway portions located beneath the pumping mechanism and the motors M and M. The plate substantially all of the mechanism located within the casing A. The driving shaft 1 is journalcd in bushlngs ca, (36 and 67 in the standards or brackets (58, ()9 and 1' 0, respectively, which are bolted. to the base-plate (it. The standards 68 and 99 are )rovided with lateral flanges or brackets 41 and 72 bolted to the front wall of the casing A. This construction forms a firm and rigid support for the journal bearings for the driving shaft 1. pumping mechanism comprises a pump casing 73 provided with pump cylinders 22. The casing 73 is preferably made of a single casting and provided with flanges 74, by means ofwhich it is bolted or otherwise The rigidly secured to the casing 60. The frontend of the pump casing is bolted to brackets 75, 76, formed on the standards 69 and- 70, respectively. The. circulation of liquid in the pumps is controlled by valves 77 ada ted to reciprocate in the valve casings 28 which latter are preferably cast integral with the pump casing 73. The pump valves 7] are operated by means of eccentric 'Z9 keyed to a shaft 80. -Piston rods 81 are pivoted at their inner ends to the valves 7? and at their outer ends are connected to the eccentric straps 82 surrounding the eccentrics 79. The eccentric-shaft is driven from the shaft 1 by means of spur gears 83 and 84 keyed to the shafts land 80, respectively. These spur gears are the same size so that the shafts will rotate together at the same angular speed. The arrangement of the eccentrics 'for operating the pump. valves on a separate shaft from the main or drivingshaft 1 is of importance in economizing space, as it permits of a much more compact arrangement, and requires much"v less room than when the valve eccentrics are mounted on the main driving shaft.

lln Fig. 2 a pump piston21is shown at the inner end of its stroke, the valve '77 being in an intermediate position. The shaft v1 rotates in a clockwise direction, and therefore as the pump piston 21 moves outward, the valve 7? is also moved outward from the position shown. Communication is therefore established between the supply chaminder, through the passages and 91, so that the/liquidis drawn from the supply chamber into the pump cylinder. By the time the pump pis ton has reached the end of its outward has beenv moved to its outermost position and again returned to the position shown. The continued rotation, of the shaft 1 moves the valve 7'? further inward and opens communiation between "the passage 91 and a passage 92., leading 77, but the eccentrics for operatino;

pressure chamber T.

operating with the cam studs 19 secured in the eccentrics "49.

from the valve chamber into the pressure chamber T. The in\ 'a rd stroke of the pi ston 21 will therefore force the liquid from the cylinder 22, through the passage 91, valve chamber and passage 92 into the pre chamber T. The operation of the pumping mechanism P therefore draws liquid from the supply chamber fl and forces it into the The rate at which the liquid is pumped depends upon tliiead iust ment of the eccentrics on the driving; shaft, the length of the piston -stroke being ad'- justable from zero to a maximum by means of the mechanism already described.

The construction of the motors h ll and M is substantially the same in many respects as that of the pumping mechanism. i these motors comprises a casing 73 secured at its inner end to the casing (50 and at its outer end to standards 69 and 70 in which the crank shafts 7 and 8 are journaled. Each motor comprises cylinder. 22, pistons 21 and piston rods 19- connecting the pisstons to the crank shafts. The motor valves ,77' are substantially like the pump valves I the motor valves are made adjustable by a construction somewhat similar to that associ ated with the driving the eccentrics I11, 1 1 and 1*)".

Referring particularly to Figs. 1, t5 and 9, it will be seen that the eccentrics 79 for operating the valves of the motor Tit l are mounted on a hollow shaft 93 and that the eccentrics 79 for the valves of the motor are likewise mounted on a hollow shaft 93. The shaft 93 is connected to be driven from the crank shaft 7 by means of intermcshing spur gears 94 and95 keyed to the shafts 93 and 7, respectively. The shaft 93 is drii 'en ,in like manner by the crank shaft 55. i i itln in the hollow shafts 93 and 93" are longitudinally adjustable rods 96 and 96*. These rods are each formed with cam slots or re cesses 12' and 13 separated by webs 1 1 coand 17 This construction issubstantially like the corresponding construction in Fig. 8, except that the parts are so disposed that the cams 16 and 17 engage an intermediate portion of the web l-l when the eccentric 79 is in a central position, so that'the eccentric may be adjusted in either direction from a central position. As shown in Fig. 9, the rod 96* has secured to its outer end a sleeve ild provided with an annular recess 99. 101 to a bracket 102 secured to the casing 'ih has one end bifurcated and provided with studs 103 engaging the slot 99. The opposite end of the lever is connected by a link or rod 10 1 to one end of a bell-crank lever 10?) pivoted at 106 to bracket 10'? secured to the casing A. Secured to the outer end of the ,rod 96 is a sleeve formed with a recess 109.

.li a ch oi shaft 1, for adjusting);

rt'lever 100 pivoted at A bell crank lever 109 pivoted'at 110 to a' is adjusted on the shaft 93 to give a full bracket lll has a bifurcated end 112 prothrow of the valve 77. The shaft 93 rol vided withfstuds engaging the recess 108. ftates in a counter-clockwise direction, and As shown in Figs. '10 and 11, a series of as it carries the valve to the right from the i hand-levers'113,- 114 and 115 are mounted position shown, communication is estab- 70 on a pivot bolt 116 secured to the casing A. lished between the pressure chamber T and The hand'levers 113 and 115 are provided the motor cylinder 22, by way of the paswith arms 117 and-118 extending below the sages 130 and 131. "This position of the pivot and connected respectively to links valve is shown'in Fig. 7. The liquid from 119 and 120, the opposite ends of which are the pressure chamber will therefore enter 75 connected tofthe bell crank levers 105 and behind the piston 21, and exert a pressure 109, respectivelylf A segmental rack121 is thereon to drivethe same forward. The secured to the casing A, and formed with throw of the valve is sufficient to fully open rack teeth 122, arranged concentric with the the port 131 so that the full pressure of the pivot 1-16. The rack 121 extends through an liquid from the pressure chamber may be 80 opening formed in an enlargement 123 of exerted on the pump piston. By the time the lever 114. The lever 114has formed inthe piston has reached the outer end of its tegral. therewith or secured thereto, se stroke, the valve 77 has been moved inmental racks'124 and 125, also arranged con- Ward and again returned to the central posicentric with the pivot. 116, and' each protion. The continued movement of this valve 86 it, and either the lever 113 or 115 may be valves 77 will be reduced.

the rod 96* longitudinally'outward, thereby this dec 9 ward or to the left, and efiect an outward die lever 114 is adjusted in either direction,

vided with rack teeth. The levers 113, 114 to the left puts the passage 131 into com1nuand 115 are each provided with a locking nication with the passage 132, extending to pawl or latch. These latches are operated by the supply chambers. The liquid in the the latch levers 126, 127v and 128, and coopmotor cylinder may therefore flow back to 25 erate with the rack teeth in the segmental the supply chamber through the passages racks 124, 121 and 125, respectively. It will 131 and 132 during the return stroke of the be seen that with this construction, when the .piston, If th ecc ntri s 79 are adjusted middle lever 114 is moved in either 'dircctoward a central position in the manner altionthe levers 113 and 11 are e rn d W hready'described, the length of stroke of the Each valve 9 operated independently ofthe other levers. therefore as it is reciprocated will only par- In Flgs. 9 and 10 the parts are shown in all tially open the port 131, so that the flow of intermediate or neutral position; that is said li id f th ur ch mber to the levers are in a centralposition and hold the motor cylinder, and also the return flow 35 IOdS 96 and 96 in an intermediate P08101011, froyn the motor cylinder "to the supply so that the eccentrics 7 ar l Concentric chamber will be restricted or throttled. with their driving sh fts f h v 1 This throttling of the liquid prevents the for example 1S mOWBd r r gi yg' 1110131011 full pressure being exerted on the piston '3 W111 be ansmltted through the 11nk'119,be11 during its outward stroke. If the motor is crank 105, rod 104 and lever 100, and move Operating t a comparatively hi h d,

v rease in pressure or throttling effect ,moving the eccentrics 79 for the valves of ill f course b h greater th t a .lh Q M rearwafdb toward! dslower speed. The throttling of the liquid l p t-s d 0f he 'Qa lng A as v ewed in during. the return stroke acts as a brake to 45 h level 113 is 111% retard the inward movement of the piston. ward directlon these eccentrics W111 be ad- Wh th eccentrics are dj t d t a ilusted lnwal'd toward the 1' tion concentric with their driving shafts, as ward movement of the lever 11 5 w ll-1n l ke indi t d i Fi 6 th l 77' ill b manner move the P0611961 longltudlnally held stationarywith the passage 131 closed,

so that there willbe no flow of liquid either l to or from the motor cylinders. This position therefore of the valve mechanism prevents any movement of the motors, the valves acting as looking devices to hold the motors stationary.

he direction of either or both of the motors M and M may be reversed by adm ggf adlustment of f the 806911 justing the eccentrics 79'. This will-readilv L I beu derstod r a 60 i The operation of the motors will be un- 5, 6 :imd 7. 1:1 r1 (iomparlson of rlgs 1g. 6 the eccentric is ad- 2 derstood from the following. description? j t d to a central position, the shaft 93 n 'p are in the P n shown being in such position that the cam studs in Fig. 2, the crank shaft 7 will be rotated 16 and 17 extend. in a horizontal direction;

in a clockw se d rection. The valve 77 is In this position t e motor piston 21- wi,ll 111 its central positlon, and the eccentrlc 79' be at the middle of its stroke, the shaft 7 adjustment of the eccentricsfor the valves of the .motor M, and a forward movement of the lever 115 would adjust said eccentrics inwardly or toward the motor. If the midthe levers 113 and 115 which are locked thereto would be carried with it and effect a n ward the supply words, the piston will be moved inwardly.

lif, however, the eccentricis adjusted to the position shown in Fig. 7, the valve 77 will be moved inwardly so as to place the motor cylinder in communication with the pressure it'll and held in adjusted started in the reverse this power transmission chamber, and the piston will therefore move outwardly.

Tt will nowbe apparent that bymeansof the hand levers shown in Fig. 11, the eccentries controllingthe motors may be adjusted "to efiiect'the operation of the two motors in unison in either direction,

and at any desired speed. The direction and speed may also be varied as desired. By moving either the lever 113 or lever 115 alone, a difi'erential' operation of the motors will be effected. The relative speeds of the motors may in this way be varied to any desired extent. or one motor may be stopped or direction, without stopping other motor, and without altering the speed of the umping mechanism. This arrangement whereby. a difierential action of the motors may be securedis of value for many purposes where it is desired to secure a differential operation of the mechanism to be driven, especially where means for readily controlling this differential action is required. For example, if mechanism were employed in propelling a boat provided with twin screw propellers, the latter could be geared to the motors M and M respectively, and the boat steered by varying the speed of the motors. Tn a similar manner the mechanism could be employed in driving and to. assist .in steering automobiles, the motors l d and M being geared to the drive wheels. f

Referring to, Fig. tit'will be seen that the pressure chamber T is provided with an i ccumulator, comprising a lo g tubular chamber or cylinder 1450, the outer end of which is preferably formed with, screw threads so that it maybe screwed in a correspondingly threaded portion 141 of the casing 60. A piston 14:2 provided with packmovable longitudinally in thecylinderllO. it piston rod 1% threaded into the piston position by a locknut 1&5 limits the outward movement of the pisin the end of the ton by engaging a. screw pressure chamber.

heavy coil spring 147 is located within the cylinder 140', and bears at its opposite ends against the piston M2 and a from the position shown- .ditions of operation. 'chamber S an accumulator comprising. a 'cylinderor tube 150 which is secured w1thi way as thereby securing a ings M3 to make the same liquid-tight is threadedplug 146 screw threaded plug 1&8 in the end of the cylinder. When the pumping mechanism is in operation, the pressure in the chamber T is suiiicient to move the piston 142 inward, and compress the spring 1&7 to a greater or less extent. The pressure in upon the rate at which the pump is forcing liquid into said chamber, upon the load on the motors, the adjustment of the eccentrics controlling the motor valves, and other conll ithin the supply in the casing in substantially the same the cylinder is secured. The

the chamber T depends...

outer end of the tube is closed by a plug 151, and the inner endis also provided with a plug 152. -A piston 153 is limited in-its, movement to the left by the plug 152. A comparatively light coil spring 154 is located in the tube 150. Ports 155 formed in the tube permit the flow of liquid into and out of the tube in front of the piston. The ac' cumulator in the pressure chamber maintains an elastic pressure on vents any the liquid, and presudden changes in pressure,

mechanism, preventing any sudden rise in pressure and consequent strain on the mechanism. It alsopermits temporary variatlon in the relative speed of the pumping mechanlsm and motors, without unduly increasing or, decreasing the pressure in the chamber T. For example, in stopping or reversing one of the motors, the rate atwhich the liquid is circulated therethrough will be decreased, causing a consequent temporary'in;

smooth operation of the p ice crease in the amount of liquid stored in the pressure chamber, which provided for by the accumulator, the piston 1&3 being moved farther inward as the pressureincreases. The accumulator in the supply chamber ti maintains only a slight pressure as the spring 154 is comparatively weak. It has been found by experience thatit is important to maintain a slight pressure on the liquid in the supply chamber. The accumulator in this chamber also serves to prevent sudden variations in the pressure and prevents a vacuum or partial vacuum being formed in the supply chamber, when the pressure in the chamber T rises.

Tn orderto prevent the pressure in the pressure chamber'Tfrom rising above a safe limit, a. relief valve it is provided which comprises a sleeveor tube one end of which has screw threaded connection 161 in a vertical portion of the partition 61 which separates the pressure and supply chambers. The movable'valv'e member 162 is provided with a valve stem 163' which extends rearwardly and is slidable freely through a threaded plug 164: which is adjustable in a threaded portion of the tube 160. A, heavy coil spring 165 surrounds the stem and bears at its opposite ends against the valve plug 164. The spring the side but is adjusted so that when the jso ' mechanism 134 (shown in Fig. 10)

pressure to the supply chamber. thereby relieving the excessive pressure. The pressure at which the relief valve operates may be variedby adjusting the plug 164. A plug 166 in the end of the casing permits the plug 146 likewise permits the removal of the accumulator in the pressure chamber. A removable plug 170 in the top of .the supply Chamber permits the operating liquid tobe supplied or replenished. The liquid used is preferably a light oil, although water or other liquid may be used if desired.

he operation of the present invention may be briefly summarized as follows :Assuming that the driving shaft 1 is being any suitable source of power, and that the parts illustrated in Figs. 3 and 10 are inthe position shown, the pumping and motors will b at rest, the eccentrics E, .E with the driving shaft. To'start the pumping mechanism, the operator moves the lever forward so that the centrics off center, and start the pumping mechanism. The levers (Figs. 10 and 11) controlling the motors M and M may now be adjusted to secureany desired operation of the motors M and M.

together at the same speed and in the same i-rection. By reversing the lever 114, the motors will be reversed, and by operating the levers 113 and 115 independently, the motors maybe independent-1y controlled to secure any desired differential action. By moving the levers toward a central position while the motors are running a powerful braking effect may be obtained. The extent of this braking action is under the complete control of the operator.

Various changes in the details of construction and arrangement of parts may obviously be made by those skilled in the art, without departing from the spirit'and scope of the invention. I wish therefore not to be limited to the particular features of construction as herein disclosed.

. What I claim as new and desire to secure y Letters Patent of the United States is 1. The combination witha her and a supply chamber closed to atmospheric pressure, of means for circulating 'a liquid through said chambers, and devices within said chambers for independently in the and E being concentric" fluid pressure mechanism for By moving the lever 114 forward, the motors will. operate -ried pressure cham-,

ber, of a device within the chamberand operable constantly to maintain a light elastic pressure on liquid in said chamber, a pressure chamber, means therein operable con tinuously to maintain a heavy elastic pressure of liquid therein, and means for circulating liquid through said chambers.

' 3. The combination with a pressure chamher and a supply chamber, of cylinders therein, a piston in each cylinder, and springs within the cylinders behind the pistons.

4. The combination of. a hollow shaft, an eccentriccarried thereby, a cam device withshaft for adjusting the eccentric, means to apply fluid pressure within the shaftto operate the cam. device, and pump,- ing mechanism operated by the eccentric and having anoutput regulated by the adjustment of said eccentric.

5. The combination witha hollow shaft, of an eccentric thereon, pumping mechanism operated-thereby, a member movable longitudinally within the shaft and prtivided with a cam surface, a cooperating member carried by the eccentric and extending into position to engage said cam surface, and operating said longitudinally movable member.

6. The combination with a hollow shaft. of an eccentric mounted thereon, pumping mechanism operated by the eccentric, a rod movable longitudinally within the shaft, and having oppositely disposed portions cutaway to form parallel inclined surfaces, studs carby the eccentric and extending into position to engage s'aid surfaces, and fluid pressure mechanism for operating said rod.

7. The combination with a hollow shaft, of an eccentric mounted thereon, pumping mechanism operated by the eccentric, a pisbetween the piston and eccentric for adjustsaid chambers during llO ing the latter when the piston is moved, and

means for supplying fluid pressure shaft to operate the piston.

8. The combination with a hollow driving shaft, of eccentrics mounted thereon, pumping mechanism operated by member movable longitudinally within the shaft and provided with cam surfaces, means carried by the eccentrics and cooperating with said cam surfaces for centrics when said member is moving, and meansfor operating said member by fluid pressure.

9. The combination with a plurality of motors operable continuously by fluid pressure, of means for supplying fluid under pressure to operate the motors, valve mechanism associated with each motor for conto the the eccentrics, a-

mower trolling the operation thereof, and means for operating said valve mechanisms to efl'ect a variation in the speed of the motors either motorsoperable continuously by fluid under pressure, of a valve associated with each motor, and operable to vary the circulation of liquid through the motor, and means for manually operating said valves eithertogether or separately.

k 12. The combination with a plurality of fluid operated-motors, of valve mechanism associated with each motor, a manually operable lever, connections between said lever and the valve mechanisms for operating the valve mechanisms of both motors together, said connections comprising additional levers either of which maybe operatedindependently of the first-mentioned lever for separatelyoperating the valve mechanisms or the two motors.

13. The combination with pumping mechanism, of vmeans for varying the rate at which liquid is delivered thereby, motors operable by said liquid, valve mechanism associated with the motors, and means for differentially adjusting the valve mechanism.

let. The comblnation. with motors, of means for supplying liquid under+ pressure to the motors, reciprocating valves controlling the circulationof liquid through the motors, and means for separately adjusting the throw of the valves to secure a differential variation in the speed or the motors.

15.-The combination with motors, of

-means for supplying fluid under pressure to operate the motors, a slide valve associated with each motor, and manually operable means for separately adjusting the throw of said valves while the motors are running.

16. The combination with a plurality of motors,of means forsupplying an operating liquid to the motors, valve mechanism associated with each motor and controlling the operation thereof, and manually operable means for operating the valve mechanisms'to charging fluid pendent mechanism in the supply tank and pressure tank to independently regulate the mechanism,

speed of the motor, 1

eflect a variation in speed or reversal of the motors either together'or separately.

17. The combination with a lever, of means for locking the lever in adjusted positions, racks carried by said lever, additional levers having the same axis of rotation as said first-named lever, locking pawls carried by said additional levers, differentially operable fluid operated mechanism controlled by said levers.

18. The combination .with a casing comprising a pressure chamber and a supply chamber, ofpumping mechanism located on one side of said casing, and a plurality of motors located on the opposite side of said casing and each comprising a plurality of cylinders and reciprocating pistons, said cylinders all being arranged in substantially the same horizontal plane.

19. In a fluid power transmission device, in combination, a pressure tank, apump operable to pump fluid under pressure to said tank, a supply tank for the pump, a motor driven by said fluid, said motor also disto said supply tank, and indepressure in said tanks.

20. In afluid power transmission device; the combination with non-rotatable pumping mechanism, of a fluid pumped: thereby, a motor driven by the fluid, a pressure pump, means operated thereby to regulate the quantity of fliiid delivered by said pumping and independent means to regulate the'speed of the motor.

21. Tn a fluid power transmission device, the combination with non-rotatable pumping 'mechanism, of a motor driven by .fluid supplied from said mechanism, a pressure manually controlled means operated thereby to regulate the quantity of fluid delivered by said, mechanism, and separatemeans manually controlled to regulate the have signed my the presence of In testimony whereof, I name to this specification in two subscribing witnesses.

auensr snunn.

Witnesses:

JOHN F. RULE, JAMES G. BETHELL. 

